This invention relates to an improved ring rail lifter mechanism which raises and lowers the ring rails on the sides of a textile yarn twister and similar machines.
There is a need for accurately raising and lowering the ring rails on textile machines such as spinning frames and twisters in a manner that forces are balanced and uneven wear is reduced on the guide posts which guide the ring rails up and down and height adjustments on one side do not effect those of the other side. One example of guides is found in U.S. Pat. No. 3,844,102. In this patent, the ring rail is supported by a bracket which is provided with opposed concave bearings which fit on either side of a guide post. A lifter tape connects the bracket to a lifter mechanism which raises and lowers the ring rail as it is guided vertically by opposing posts. The downward force of the ring rail forces the concave bearings into contact with opposite sides of the guide post. However, in this mechanism the concave bearing rolls are always in high load-bearing contact with the guide posts. Uneven wear often results interferring with accurate up and down travel. U.S. Pat. No. 3,022,625 shows a ring rail suspension having similar load bearing characteristics.
U.S. Pat. No. 2,770,093 discloses a high lift suspension system for ring rails on a spinning frame for large yarn packages. Independent upper and lower slides for raising and lowering the ring rails are joined together by adjustable tie rods. The tie rods may be adjusted to conform to the spacing between the samsons. This is said to eliminate the need for accurately spacing opposing samsons in order to achieve free movement of the slides along the samsons. The tie rods are spring loaded to urge the slides in contact with the samsons. This is to keep yarn guide rings on the rail concentric with the yarn package formed. U.S. Pat. No. 3,974,633 relates to a textile yarn twister having vertical slides joined by bars whose length is not adjustable.
The prior art has somewhat approached the problem of inaccurately spaced vertical guide posts and the forces of the slides on the guide posts. The uneven wear of the guide posts or samsons and the accompanying interference with reciprocating vertical motions while providing means to set the reversal points independently for each side has not been satisfactorily addressed.
Accordingly, an object of the invention to provide a suspension assembly for raising and lowering the ring rails of a textile yarn processing machine in unison with reduced guide post loading and wear and which is easy to adjust.
Another object of the invention is to provide a suspension assembly for raising and lowering the ring rails on a textile twister and the like which balances forces between the slide bearings and the guide posts generally eliminating loads and wear on the guide posts.
Still another object of the invention is to provide a parallelogram linkage assembly having adjustable connector rods to connect the front and rear ring rails of a textile yarn twister so that height adjustment of the rails on one side do not effect the other side and where the ring rails may be raised and lowered in unison without undue stress on the guides.
These and other desirable objects of the invention will be apparent from and/or inherent in the descriptions and explanations which follow.